TROUBLESHOOTING
9
PROBLEM CAUSE SOLUTION
Errac / Inaccurate
Weight Readings
The vehicle is not parked on
a level surface
Park on level concrete ground.
Parking on sloped or banked
surfaces will cause the vehicle weight distribuon to shi
between the axle groups. Addionally,
if one or more of the
vehicle’s wheels are in a pothole, that could result in addional
pressure or torque on the suspension air bags. This will cause the
suspension to have a different air pressure than what is normally
needed to hold up the given weight.
The vehicle’s brakes are on
Release the parking brakes when weighing and/or calibrang.
When the vehicle brakes are set, they could apply addional
pressure or torque on the suspension air bags. This will cause the
suspension to have a different air pressure than what is normally
needed to hold up the given weight.
There is a significant air leak
in the suspension system
Check air lines for leaks. Having a leak could cause the
HCV to
refill the suspension at regular intervals to maintain the vehicle’s
ride height. If there is a significant leak, the gauge display will
slowly decrease in value and then quickly increase in value when
the HCV refills the suspension system.
The Height Control Valve
(HCV) is malfunconing or
broken
If the HCV is not funconing correctly, the air pressure applied to
the suspension system could be inconsistent and/or errac. To
test for an HCV problem, acquire a weight reading from the Right
Weigh gauge and write it down (refer to gauge operang
instrucons for proper procedure). Drive the vehicle around the
block and return to the same locaon. Acquire a second reading
from the Right Weigh gauge. If the two readings are significantly
different, then the HCV might be malfunconing.